27.近場長度(near-zone length,NZL)的計算式是:
(A)NZL=0.5×換能器口徑(aperture)÷波長(wavelength)
(B)NZL=0.5×換能器口徑(aperture)平方÷波長(wavelength)
(C)NZL=0.25×換能器口徑(aperture)平方÷波長(wavelength)
(D)NZL=0.25×換能器口徑(aperture)÷波長(wavelength)
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統計: A(100), B(329), C(779), D(34), E(0) #1050506
統計: A(100), B(329), C(779), D(34), E(0) #1050506
詳解 (共 3 筆)
#6319790
NZL=0.25*(ap)2/ λ
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